Sound Levels in the Pediatric Cardiac Critical Care Unit and Their Correlation With Sedation Administration, Delirium Scores and Patient Heart Rate

This study aims to measure and average sound levels during hospitalization in the Children's National Pediatric Cardiac Intensive Care Unit (CICU) and investigate any correlation between heightened sound levels, the incidence of delirium, the administration of sedation medications given for agitation, and patient heart rate changes. Recognition of modifiable risk factors, such as sound levels, can lead to the development of preventive strategies to keep sound levels within recommended guidelines and to lessen the amount of sedation medications that are given for agitation. Successful completion of this research will contribute to the development of modifiable environmental factors for the prevention of oversedation and delirium in critically ill children, potentially improving outcomes in a vulnerable patient population. This will be the first study of this nature performed in a large CICU and the first to look at delirium scores and vital sign changes as related to sound levels.

Many studies have shown that increased sound levels in hospitals can worsen patient agitation and lead to sleep disturbance and impair rest and healing. The World Health Organization and the Environmental Protection Agency mandate that hospital sound levels not exceed 40-45 decibels dB(A) during the day and 35 dB(A) at night. Previous studies in four European ICUs with adult patients showed that ICUs demonstrated higher than recommended sound levels 50% of the time, with an average sound level of 51 dB(A) over 24 hours and a peak sound level of 85 dB(A). In the only published study on sound levels in a pediatric CICU and their relationship to sedation administration, Guerra et al showed in 2017 that mean levels were over 59dB in both open patient areas as well as single rooms with little variation between day and night levels and that a higher peak and average sound level correlated with more sedation boluses in the subsequent 2 and 5 hours respectively.

The association between neurotoxicity and the use of sedatives and analgesia in young infants with congenital heart disease has also been described. In addition, there are appreciable negative hemodynamic effects of oversedation on the pediatric patient recovering from cardiac surgery. For this reason, it is important to investigate the impact that sound levels might have on sedation administration. Along with this, as vital sign changes such as an elevated heart rate can lead to patients receiving additional sedation, it is equally important to study the relationship between patient heart rate and sound level in a cardiac intensive care unit.

Delirium is defined as an acute and fluctuating change in attention, thinking, perception, and consciousness secondary to an underlying medical condition. The consequences of delirium have been well studied in the adult critical care population, and include prolonged hospitalization time, difficulty with long-term thinking, increased days of mechanical ventilation, and increased risk of death after discharge from the hospital. In adult intensive care units, delirium screening is routinely performed because of the known consequences of the disease. With the advent of the Cornell Assessment of Pediatric Delirium (CAPD), there is now a rapid and reliable method of screening for delirium in pediatric intensive care units. Since 2018, bedside nurses in the Children's National CICU have been trained to calculate CAP-D scores. This delirium assessment performed once per shift, can be analyzed side-by-side with average sound levels over that same shift to assess for any correlation between these two parameters.